This project will use the techniques of epidemiology and clinical decision analysis to study the management of infants with hypoplastic left heart syndrome (HLHS), a congenital heart disease which if untreated is uniformly fatal. The broad objective is to determine the optimal surgical approach to treatment, based on mortality and morbidity comparisons of two strategies: staged reconstructive surgeries or heart transplantation. Specific aims are to demonstrate how improved surgical technique and postoperative care have lowered mortality over time, compare current mortality rates between strategies, determine predictors of mortality, the limitations inherent in each strategy, the problems surviving children and their caregivers face, and predictors of morbidity. The project design is a review of the medical records of all patients born with HLHS between 1989 and 1993, admitted to one of the four participating pediatric cardiac surgery centers with an intention to treat surgically. Specific preoperative and postoperative factors will be compared in multivariate analysis as predictors of mortality and morbidity for each strategy. The research will produce a scientific report with a complete literature review and support the creation of a decision tree to determine the better surgical strategy based on individual preoperative characteristics.